1. Field of the Invention
The present invention relates generally to medical devices and methods of use thereof. Specifically, the present invention relates to medical devices used to create a seal around an incision for performing an end-to-side anastomosis procedure on the aorta or other blood vessel.
2. Description of the Related Art
Currently, the standard practice in performing a coronary artery bypass surgical procedure is to open the patient""s chest, place the patient on a cardiopulmonary bypass (heart-lung) machine, stop the heart from beating, and then attach the coronary artery bypass graft(s) to the aorta and coronary arteries. The heart-lung machine is needed to maintain the blood circulation through the patient and to provide gas and heat exchange surfaces. Typically, the blood is cooled using the heart-lung machine to slow down the metabolism of the patient. Additionally, the blood is oxygenated and carbon dioxide is allowed to be released from the blood. The aorta is usually clamped proximal to the entrance point of the blood from the heart-lung machine.
There can be numerous complications with stopping the patient""s heart and using a heart-lung machine. The heart-lung machine typically needs to be primed with blood. This is usually done with blood from a blood bank which can be contaminated with infectious agents such as the HIV virus. The heart-lung machine can lyse red blood cells and destroy platelets causing anemia or increasing the risk of hemorrhage. The clamping of the aorta can release plaque into the blood stream, which can cause a stroke or a peripheral vascular incident.
Another technique is to partially cross-clamp the aorta with a xe2x80x9cUxe2x80x9d shaped clamp such that a small blood tunnel is created and an area of blood stasis is created for making a proximal anastomosis site. This technique eliminates the heart-lung machine, but increases the risk of plaque releasing into the blood stream.
Thus, it is desirable to have a device and method that greatly reduces the risks associated with coronary artery bypass surgical procedures.
The present invention relates to a device and method for creating an anastomosis site along a wall of a blood vessel without interrupting the flow of blood through the blood vessel. The device may be used in various applications which involve incisions made in the aorta, other blood vessels or organs. The device is particularly suited to create an anastomosis site for coronary artery bypass grafts without obstructing the flow of blood in the patient""s aorta. Thus, the device may be used while the patient""s heart is beating without the use of a heart-lung machine or a cross clamp.
In a preferred embodiment, the device comprises an extruded hollow tube with a wire or shaft which slides within the tube. A flexible inverting member is attached to the distal end of the tube and coupled to a distal end of the shaft. A proximal portion of the shaft is coupled to an actuation assembly of the device, which preferably comprises a handle. By manipulating the handle, the practitioner can remotely deform the inverting member between two different configurations: an elongated, narrow configuration in which the inverting member may be advanced through a small incision, and an expanded, inverted configuration in which the inverting member forms a cup that can be used to form a sealed pocket against the inner wall of a blood vessel.
In operation, the medical practitioner inserts the inverting member into the blood vessel through an incision while the inverting member is in its elongated, narrow configuration. The medical practitioner then manipulates the translatable shaft inside the hollow tube, or alternatively, the hollow tube itself, (preferably by manipulating a handle of the device) to expand the inverting member into its inverted configuration. The practitioner then applies a proximal force to the device to cause a seal to be formed by the radial rim of the inverting member pressing against the inner wall of the blood vessel. This prevents blood from flowing out of the incision, without obstructing the flow of blood in the blood vessel, and creates a working area for performing an end-to-side anastomosis.
In one embodiment, the device includes a hole puncher which is slidably mounted on the hollow tube. Once the seal has been formed inside the blood vessel, the hole puncher is slidably advanced distally to the outer surface of the blood vessel, and is then actuated to form an anastomosis hole around the entry point of the tube. The hole can alternatively be formed manually using a scalpel or other cutting device. In either case, the hole falls within the boundaries of the inverting member""s rim, and is thus isolated from the flowing blood in the blood vessel.
Once the anastomosis hole has been formed, a bypass graft is loosely sutured around the outside of the hole while the seal is maintained between the inverting member""s rim and the blood vessel""s inner wall. The inverting member is then returned to the elongated, narrow configuration and withdrawn from the hole, and the ends of the suture are pulled tight to cause the end of the graft to contact the blood vessel.
These and other features and advantages of the present invention are more fully set forth in the following Detailed Description and the accompanying figures in which similar reference characters denote similar elements throughout the several views.